The present invention relates to electronic price label (EPL) systems used in transaction establishments, and more specifically to a communication device and method for EPL systems.
EPL systems typically include a plurality of EPLs for each merchandise item in a store. EPLs typically display the price of corresponding merchandise items on store shelves and are typically attached to a rail along the leading edge of the shelves. A store may contain thousands of EPLs to display the prices of the merchandise items. The EPLs are coupled to a central server from where information about the EPLs is typically maintained in an EPL data file. Price information displayed by the EPLs is obtained from the PLU file.
EPLs today may be wired or wireless. Wireless EPLs may employ infrared or radio frequency (RF) transmitters. EPLs systems of the assignee of the present invention employ RF transmitters and modulated backscatter techniques. An EPL computer transmits polling signals to one or more EPLs. In order to respond to the poll, an EPL xe2x80x9creflectsxe2x80x9d the polling signal back to the EPL computer within a predetermined time interval of receiving the polling signal. A good analogy of the RF modulated backscatter acknowledgment signal is a mirror reflection. If two men face each other, one with a flashlight and the other with a mirror, the man with the mirror can send an acknowledgment to the man with the flashlight by reflecting the beam of light back to him. Similarly, the man with the mirror may indicate the opposite by not reflecting the light of the flashlight.
Modulated backscatter techniques are taught in U.S. Pat. No. 5,640,683, to Evans et al., entitled xe2x80x9cModulated Backscatter Wireless Communication System Having An Extended Rangexe2x80x9d, issued Jun. 17, 1997. This patent is hereby incorporated by reference.
Remote control and communication with a host EPL computer system would be desirable anytime the EPL system installer, user, or administrator is performing EPL related tasks away from the host EPL computer. One such task that might be performed by an EPL system administrator is adding or removing an EPL tag to a shelf. Normally, the administrator must perform administrative tasks at the host processor before placing the tag on the shelf. These tasks include initializing the EPL tag and adding the ID of the EPL tag to an EPL database. It would be advantageous to perform these administrative tasks remotely as the system administrator is adding or removing the tag from the shelf.
Hand-held terminals have been developed which communicate with the EPL computer, effectively allowing remote communication with the host processor. However, these terminals are costly and can introduce noise that may interfere with the EPL system. When a hand-held terminal device is introduced that does not share the same communication protocol or hardware as the EPL system, there is some likelihood that the device will interfere with existing EPL system communication. In order to avoid interference, the EPL system must sacrifice performance by giving up radio frequency bandwidth to the device.
Therefore, it would be desirable to provide a communication device and method for EPL systems that would allow an operator to remotely control the EPL computer from anywhere in a store using the existing EPL infrastructure.
In accordance with the teachings of the present invention, a communication device and method for EPL systems is provided.
The device includes a microcontroller, a first EPL circuit enabled by the microcontroller which sends a first signal to an EPL computer in response to a first polling signal from the EPL computer indicating that data from the microcontroller is ready for transmission, a number of second EPL circuits which store the data from the microcontroller and which send the data to the EPL computer in response to a second polling signal from the EPL computer, a third EPL circuit which receives a second signal from the EPL computer acknowledging receipt by the EPL computer of the data, and which signals the microcontroller of the receipt of the data, a keypad coupled to the microcontroller for recording the data from an operator, and a display for displaying the data as it is recorded and for displaying an indication of the receipt of the data.
The device may be used as a remote control device in which the data includes functions to be executed by the EPL computer from a list of functions maintained by the EPL computer.
In more detail, the second EPL circuits each include a first portion including first control circuitry having a first unique address and a first state out of first and second operational states, and a second portion including second control circuitry having a second unique address and a second state out of the first and second operational states. The EPL computer interprets a binary data xe2x80x9c0xe2x80x9d when the first state is equal to the first operational state and the second state is equal to the second operational state, and interprets a binary data xe2x80x9c1xe2x80x9d when the first state is equal to the second operational state and the second state is equal to the first operational state.
The method of the present invention includes the steps of loading a number of EPL data circuits having first and second portions with a portion of data by a microcontroller, and transmitting the data to the EPL computer by the EPL data circuits in response to a polling message from the EPL computer. Loading involves the substeps of enabling acknowledgment of polling messages by the first portions of a first group of the EPL data circuits and disabling acknowledgment of the polling messages by the second portions of the first group of EPL data circuits to form a data value equal to zero, and disabling acknowledgment of polling messages by the first portions of a second group of the EPL data circuits and enabling acknowledgment of the polling messages by the second portions of the second group of EPL data circuits to for a data value equal to one.
It is accordingly an object of the present invention to provide a communication device and method for EPL systems.
It is another object of the present invention to provide a communication device and method for EPL systems which would allow an operator to remotely send data to an EPL computer from anywhere in a store.
It is another object of the present invention to provide a remote control device and method for EPL systems which would allow an operator to remotely control an EPL computer from anywhere in a store.
It is another object of the present invention to provide a communication device and method for EPL systems that utilizes the existing EPL infrastructure.